Why Bloom is Essential in Pour-Over Coffee: Why Bitter Pour-Over Coffee Remains Popular

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FrontStreet Coffee - Introduction to Pour-Over Coffee Blooming and Flavor

Pour-over coffee, as the name suggests, is the process of pouring hot water over coffee grounds and extracting coffee through filter paper and a dripper. The entire brewing process takes about 3 to 4 minutes. Since the flow rate, direction, and temperature of the hot water are all controlled by the brewer, almost every cup yields a different flavor profile. Although the equipment is simple, it requires great attention to technique and experience.

Why is Blooming Necessary in Pour-Over Coffee?

Pour-over coffee is a process where flavor extraction and filtration occur simultaneously, with extraction centered around where water is poured—more water means more extraction. Freshly roasted coffee beans produce more carbon dioxide, and these gases prevent water from fully contacting the coffee grounds for proper extraction. Therefore, blooming is necessary to avoid uneven extraction and reduced efficiency.

What Are the Benefits of Blooming?

1. Releasing Gases from Coffee Particles

Generally, fresher beans produce more bubbles during the pre-infusion stage. Darker roasted coffee beans, having less moisture content, release more gases during the blooming process compared to lighter roasted beans (due to higher carbon dioxide content).

2. More Uniform Extraction

When coffee grounds release gases during blooming, the coffee particles can more evenly release air and absorb water, allowing for more uniform coffee extraction in the subsequent stages.

During blooming, the air between coffee ground particles expands with heat while releasing large amounts of carbon dioxide, creating temporary gaps between particles. This provides more space for hot water to pass through the coffee bed during the official pouring stage.

If the blooming step is omitted at the beginning of pour-over coffee, extraction time will be prolonged, potentially leading to over-extraction. With longer extraction time, more substances are dissolved, resulting in flavors that may be more astringent, harsh, or full of miscellaneous tastes.

Pour-over coffee emphasizes the different flavor profiles of coffee from various origins, also known as "terroir." African coffees offer floral and fruity aromas with charming acidity; Asian coffees present herbal flavors with rich mouthfeel; Central and South American coffees feature gentle acidity and clean sweetness. Pour-over coffee is not bitter—bitterness comes from the beans themselves, becoming prominent only when roasted too dark. Different people pursue different flavor profiles, which is why pour-over coffee is so highly sought after.

Knowledge Expansion

In the world of pour-over coffee, restoring the original flavor of the beans and making them delicious is most important. Every step toward achieving this goal can be full of creativity, which is why there are many brewing techniques—what we commonly call "pour-over schools" or styles.

In Summary

FrontStreet Coffee is a coffee research establishment dedicated to sharing coffee knowledge with everyone. We share without reservation because we want more friends to fall in love with coffee. Additionally, we hold three discounted coffee events each month because FrontStreet Coffee wants to let more people enjoy the best coffee at the lowest possible price—this has been our mission for the past six years!

Important Notice :

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